Respiratory masks



Oct. 2, 1962 G. E. J. DICKINSON 3,056,402

RESPIRATORY MASKS Filed May 26, 1959 2 Sheets-Sheet 1 Z f f g wm O 2, 1962 G. E. J. DICKINSON 3,056,402

RESPIRATORY MASKS Filed May 26, 1959 2 Sheets-Sheet 2 lenior W Unite hoe 3,056,4ti2 RESFIRATGRY MASKS George Edmund .lolnr Dickinson, Sawhridgeworth, England, assigns: to Airmail Limited, Harlow, England Filed May 26, 1959, Ser. No. 815,831 8 Claims. (Cl. 128-141) This invention relates to respiratory masks and particularly to means for attaching such a mask to a support adapted to be attached to the head of the wearer so as to hold the mask firmly against the face. The support adapted to be attached to the head of the wearer may be a flying helmet, but it is usually more satisfactory to use a head-harness carrying telephone housings which are held close to the ears of the wearer when the headharness is in use.

It is very desirable, particularly in oxygen masks for aircrews, that the wearer should be able to fit and remove the mask easily and quickly, and that the mask should hang easily on the wearers chest when not in use so as to cause no inconvenience and yet be always ready for use.

The principal object of the present invention is to provide improved means for attaching a mask to a support comprising a toggle linkage that can be tightened to hold the mask firmly in position on the wearers face or loosed so as to break the toggle and thereby allow the mask to fall from the wearers face. Another object of the invention is to provide means for attaching a mask to a support having flexible tie means which is held in tension when r the mask is in working position on the wearers face but hangs freely when the mask is removed from the wearers face.

The invention will be fully understood from the following more detailed description of one example of a headharness and respiratory mask embodying the invention, reference being made to the accompanying drawings in which:

FIGURE 1 is a side elevation showing the respiratory mask attached to the head-harness and fitted in working position on the wearers face,

FIGURE 2 is a similar view showing the respiratory mask still attached to the head-harness but removed from the wearers face, and V FIGURE 3 is a front view corresponding to FIGURE 2 showing the respiratory mask with part of the means for attaching it to the head-harness.

In the drawings, 1 is a head-harness which includes a resilient head-band 2 adapted to clip on to the head of the wearer and carrying ear-pieces 3 which are held close to the ears of the wearer when the head-harness is in use. Each ear-piece consists of a telephone housing 4 and is in use. Each ear-piece consists of a telephone housing 4 and an ear pad 5 adapted to cover the Wearers ear. The ear pad may be a sponge-rubber pad designed to shut out noise. The part 6 is a pad designed to support the weight of the head-harness comfortably to the wearer and the part 7 is a counter-pressure band which passes round the back of the head of the wearer and takes the pull of a linkage by which a respiratory mask attached to the harness is held in position against the face of the wearer.

The mask proper comprises a rubber face-piece 8 moulded to the face of the wearer which is supported by a rigid metal former 9 and to which an oxygen pipe 19 and a telephone lead 101 are connected. The telephone lead is connected to a microphone or other telephone transmitter mounted within the former 9.

A toggle linkage is provided for attaching the mask to the head-harness. This comprises a compression link 11 and a flexible tension link 12 at each side of the mask, the two compression links 11 being hinged to the former 9 at one end and so that they are free to swing up and down at the other end, and the tension links 12 being attached at one end to the free ends of the links 11 and at the other end to the ear pieces 3 of the head-harness. For simplicity of construction, the compression links 11 are formed by the legs of a U-shaped bent-wire frame having a cross member 13 by which the links 11 are yoked together so that they must swing up and down as one. Two loops 14 are formed in the wire at the junctions between the links 11 and the cross member 13 to provide a means of attachment for the tension links 12. The links 11 are bent at right-angles as shown to form angular projections 15 which bear against the front wall of the former 9 when the links are swung downwards to the position shown in FIGURE 1.

Each tension link 12 is composed of a length of chain 16 attached at one end to one of the loops 14, and an eye 17 attached to the other end of the chain by an adjustable tensioning device 18. The eyes 17 are adapted to be attached to the head-harness by means of safe hooks 19 provided for them on the telephone housing 4. The tensioning devices 18 are adjustable in length for a purpose hereinafter to be described and the hooks 19 are constructed so that they can be opened to permit detachment of the eyes 17 when desired but are normally securely closed so as to prevent accidental detachment of the eyes.

The head-harness is designed to be attached to the head of the wearer in the manner shown in FIGURES l and 2 and the mask is adapted to fit over the nose and mouth of the wearer when in use in the manner indicated in FIGURE 1. The position of the hinge 20 by which the compression links 11 are attached to the former 9 is arranged to be somewhat above the level of the centre of the face-piece 8 and the angular projections 15 are arranged to co-operate with the front wall of the former 9 to arrest the downward swinging movement of the links 11 in a position in which their outer ends lie in a plane (indicated by the broken line 21 in FIGURE 1) which passes through the junctions between the eyes 17 and hooks 19 and passes approximately through the centre of the face-piece 8.

The tension links are considerably longer than the compression links 11 so as to be capable of extending from their points of attachment to the hooks 17 to the forward extremities of the compression links 11. They are thus capable of co-operating with the compression links to form toggles capable of holding the face-piece firmly against the face of the wearer. The tensioning devices 18 can be adjusted to suit the wearer and to obtain the degree of pressure required to prevent leakage round the edges of the mask, and the arrangement of the links 11 so that their forward extremities lie in the plane 21 (FIGURE 1) abovereferred to ensures that the pressure is applied evenly.

It will be observed that the toggle formed by the links.

11 and 12 has a dead-center position, indicated by the line 22 in FIGURE 1, which can be reached by rocking the free ends of the links 11 upwards from the limiting position in which they are stopped by the engagement of the angles 15 with the front surface of the former 9. The toggle is thus normally locked in the position shown in FIGURE 1. In other words, the stop formed by the angles 15 and the surface of the former 9 prevent breaking of the toggle by downward movement of the front ends of the links 11. However, the links 11 can be moved upwards beyond the dead-center position and the toggle can thus be broken when desired by simply pushing the links 11 upwards.

When the tensioning devices 18 have been adjusted to suit the wearer the mask can be quickly fitted by simply placing the mask in position on the wearers face and then rocking the links 11 downwards to the position shown in FIGURE 1 so as to tighten the toggle. The mask can be just as easily removed by simply pushing the links 11 upwards so as to break the toggle and so allow the mask to fall away from the users face and rest against his chest as shown in FIGURE 2. The flexible chains 16 allow the mask to hang easily on the wearers chest and permit much greater freedom of movement of the head than would be possible with a rigid toggle linkage.

The part shown at 23 in FIGURES 1 and 2 is a boom microphone which may conveniently be attached to one of the telephone housings 4 so that it can be swung up out of the way when the respiratory mask is in use but can be brought down to a position near the wearers mouth when needed for use instead of the microphone provided in the respiratory mask.

I claim:

1. A respiratory mask provided at each side with a toggle composed of two pivoted links capable of holding a face-piece firmly against the face of the wearer, one link being a compression link extending forward from a point of attachment to the face piece and the other being a flexible tension link extending forward from a point of attachment to a support for attachment to the head of the wearer, movement of the compression links being limited by stop means which prevents breaking of the toggle by downward movement of the front ends of the links but allows the toggle to be broken by an initial upward movement of the front ends of the links to detach the mask from the face when required.

2. A respiratory mask according to claim 1, wherein said flexible tension link includes a length of chain.

3. Means for attaching a respiratory mask to a support for attachment to the head of the wearer, comprising a toggle linkage having a pivoted compression element and a flexible tension element and capable of holding a mask firmly against the face of the wearer with both elements extending forwards from points of attachment respectively to the respiratory mask and to the support, movement of said compression element being limited by stop means which prevents breaking of the toggle by downward movement of the toggle elements but allows the toggle to be broken by initial upward movement of the front ends of the elements to detach the mask from the face when required.

4. The combination comprising a support for attachment to the head of a wearer, a mask body, a pair of compression links hinged to said body on opposite sides thereof for up and down swinging movement thereon, the hinged connection between said compression links and said body being disposed above the centre of the mask body, a pair of flexible tension links each attached at one end to the free end of one of said compression links and adapted to be fastened at its other end to said support, means for adjusting the lengths of said tension links, and stop means limiting the downward swinging movement of said compression links at a position in which the points of attachment of said compression links to said tension links are located in front of the mask and below the level of the hinged connection between said compression links and said body.

5. The combination comprising a support for attachment to the head of a wearer, a mask body, a frame pivotally attached to said body for swinging movement up and down in front of said body, a pair of flexible tension elements attached to said frame at opposite sides of said body and adapted for fastening to opposite sides of said support, and stop means limiting the downward swinging movement of said frame at a position in which the points of attachment of said flexible elements to said frame are located in front of and below the points of attachment of said frame to said body.

6. The combination including a support for attach ment to the head of a wearer having ear pieces located close to the ears when the support is in use, a respiratory mask adapted to fit over the nose and mouth of the wearer when in working position, and a toggle linkage for fastening said respiratory mask to said support, said toggle linkage including a compression member hinged to said mask for pivotal movement up and down in front of said mask, a pair of flexible tension members located on opposite sides of said mask and capable of attachment at one end to said ear pieces and at the other end to said frame, and stop means for limiting the downward movement of said compression member at a position such that when said mask is in the working position the points of attachment of the tension members to the ear pads and compression member respectively are located in a plane below the hinged attachment of said compression member to said body.

7. The combination including a support for attachment to the head of a wearer having ear pieces located close to the ears when the support is in use, a respiratory mask adapted to be pressed against the wearers face when in working position and a toggle linkage for fastening said respiratory mask to said support, said toggle linkage being movable through a dead-center position and including a compression member hinged to said mask for pivotal movement up and down through said deadcenter position, a pair of flexible tension members on opposite sides of said mask adapted to be fastened at one end to said ear pieces and fastened at the other end to said compression member, and stop means for limiting the downward movement of said compression member after it has passed down through said dead-center position.

8. The combination comprising: a head harness, a breathing mask, a toggle lever pivotally mounted on said mask for limited forward and downward swinging movement, a flexible tension member connected with said head harness and said toggle lever for holding said toggle lever in its limited position past dead center with the mask fitted to the face of the user and for supporting said mask upon reverse movement of the toggle lever past dead center for permitting removal of the mask from the face.

References Cited in the file of this patent UNITED STATES PATENTS 2,814,293 Gabb et al. Nov. 26, 1957 

